How Do the New Pallet Rack Fire Codes Affect Your Rack Design?

NFPA 13 – Updated Pallet Rack Fire Codes Take Aim at Warehouse Safety

The National Fire Protection Association (NFPA) is a trusted global organization that issues fire codes and safety recommendations followed by warehouse design and installation crews. In 2020, there were approximately 1450 fires reported at warehouse properties amounting to over $283 million in property damage, 16 civilian injuries, and two deaths. In response to warehouse fire safety concerns, the NFPA recently released new pallet rack fire code guidelines to reduce those statistics.

The 2022 update addresses several changes to their NFPA 13 Standard for the Installation of Sprinkler Systems that directly impact pallet racking systems. Please see NFPA 13 for a full report of all sprinkler system standards. Here is a recap of the directives and how they relate to different rack design scenarios.

Fire Suppression for Warehouse Pallet Racking

The NPFA pallet rack fire code for new systems delineates when ceiling-level sprinklers and flue spaces are sufficient and when in-rack sprinklers or other mitigating devices are necessary based on system height and depth.

Ceiling-Level Sprinklers & Flue Space Requirements

Water from ceiling-level sprinklers penetrates the pallet rack via open longitudinal and transverse flue spaces. As the graphic shows, longitudinal is the vertical space behind a rack row and between back-to-back rack systems. Transverse flue space is the horizontal area between stored items. Maintaining these open flue areas is vital for early fire suppression and fire mitigation.

However, the NFPA recognizes the difference in water penetration from ceiling-level sprinklers in loaded vs. unloaded rack, even with the flue spaces. The new regulations specifically address this by recognizing that palletized material acts as a shelf, hindering water penetration from ceiling-level sprinklers. Therefore, the NFPA has designated some deep rack systems as “solid shelving” requiring in-rack sprinklers in certain instances. See below for details.

Ceiling-Level Sprinklers Only

For systems that are no higher than 25ft high and have a depth of 20ft or less, in-rack sprinklers are not required under the following conditions:

Single Row Rack

All transverse flue spaces are a minimum of 3in through the height of the rack. The maximum distance between transverse flue spaces is 5ft horizontally.

Double-Row Rack

All transverse flue spaces are a minimum of 6in through the height of the rack. The maximum distance between transverse flue spaces is 5ft horizontally.

Pallet Rack Fire Codes: Front Elevation and Sprinkler Blueprints

Multiple-Row Rack

For racking systems greater than one pallet deep, a minimum of 6in wide vertically aligned transverse flue spaces must be maintained throughout the height of the rack. The flue spaces must not be more than 5ft apart. No longitudinal flue is required for system depths that do not exceed 20ft. In addition, a 3’6″ gap every 20′ is required to separate the rack –meaning, you must put a 3’6” gap between systems when you have two multiple row systems that are 20′ or less backed up to each other. See image below.

Pallet Rack Fire Codes: Side Elevation and Sprinkler Blueprints

For systems greater than 20ft deep, a 6” longitudinal flue is required every 5ft of the system depth.

Pallet Rack Fire Codes: Front Elevation and Sprinkler Blueprints

See the Fire Baffle section below for alternative design options for systems 20’ deep or more.

NOTE: You will see a consistent reference to well-maintained flue spaces between the stored inventory. Apex can help you with lane dividers and backstops to ensure your system remains compliant with the NFPA pallet rack fire codes. Talk to your Apex representative about pallet rack safety products to enhance your rack function.

Fire Baffles & In-Rack Sprinkler Requirements

When designing and installing multiple-row racking, NFPA requires in-rack sprinklers for systems deeper than 20ft and taller than 25ft high. However, if the following parameters are met, fire baffles may provide a cost-effective solution to in-rack sprinklers:

6in transverse flue space every 5ft
Limit the depth to 20ft
Ensure 3ft 6in of longitudinal flue space every 20ft to separate the rack
Install a vertical barrier every 20ft in the back of the rack
- Barrier options – 3/8in thick 22ga sheet metal or 10mm plywood/particle board or equivalent.
- Must start a maximum 4in above the floor and extend the height of the rack
- Must span the entire length of the row

Full Height Fire Baffles - Apex Companies

Full Height Fire Baffles – See New NFPA Requirement for Dense Rack Systems

If your storage rack is taller than 25′ high and deeper than 20′, your most economical solution may be a pallet shuttle system — see details below.

Other Alternatives

PEAK Shuttle Semi-Automated Pallet Storage

PEAK Shuttle is another option to consider for deep-lane, high-density storage where you cannot install a vertical fire baffle. The automated shuttle system is programable to add the required gap between the pallets to secure the transverse flue space requirement.

Shuttle systems provide quick, accurate pallet storage and retrieval with minimal labor expense. PEAK is semi-automated and scalable to meet efficiency and safety goals. Talk to your Apex representative for more information about PEAK shuttle systems.

Sprinkler Head Density

An additional change in the NFPA pallet rack fire codes addresses sprinkler head density in new construction. It represents a shift from the previously used density/area curve calculation to a single-point method. Density is calculated as the per-minute water flow for every square foot of space. Existing pallet rack systems remain under the previous density/area curves recommendations.

Sprinkler design for a racking storage system is predicated on the class of materials in that space vs. an occupancy number, as would be for a typical building design. Everything from the inventory to the packing material and container creates the classification designation.

As sprinkler system technology has advanced in recent years, rack designers can more closely tailor the water delivery to the fire risk of the materials… and comply with NFPA regulations.

Next Steps – Protect Your Warehouse Facility & Team from Fire Damage

Vertical Steel Fire Baffle

Pallet rack design and installation will get you far in protecting your facility from fire damage, but once that building is operational, the burden of safety shifts to the building owner or designated representative. Ensure your team is ready with these steps:

Designate responsible parties to monitor, inspect, and maintain/repair fire safety equipment.
Conduct regular fire safety training, including practiced evacuation plans with your team.
Clearly mark all exits, egress lanes, fire alarms, and fire extinguishers.
Ensure exits and egress lanes are free from obstacles.
Ensure emergency lighting is installed and maintained; properly illuminate work areas.
Be aware that changes in the class of materials you are storing may affect the type of fire safety/suppression system required.
Consider installing fire baffles within your pallet racking system design.

Let the Apex Team Take the Heat Off

Call us crazy, but we love our work. We are proud to be able to design, install, and maintain pallet racking and processing systems that improve the flow and efficiency for our customers. Part of that responsibility is staying on top of changes to the pallet rack fire codes from the NFPA to ensure our customers receive safe, effective systems.

Call Apex to schedule a free warehouse or rack system design consultation. We have offices throughout the U.S. to ensure prompt, expert service.

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